Method of expanding metal



Dec. 3, 1929. GERSMAN 1,737,998

METHOD OF EXPANDING METAL Filed Oct. 9, 1926 2 Sheets-Sheet 1.

gmwmtoz fiAFI/EY m ems/mm Dec. 3, 1929. H. M. GERSMAN METHOD OFEXPANDING METAL Patented Dec. 3, 1929 UNITED STATES PATENT ()FFEQ METHODEXPANDING METAL Application filed October 9, 1926. Serial No. 140,522.

This invention relates to a method of expanding metal wherein theexpansion is effected in connection with the elongation of the strands.The invention is generically applicable to the production of expandedmetal articles of difierent kinds and for clifferent uses in structuraloperations, and is herein claimed in its generic aspect and also in onespecific aspect, namely, the production of expanded metal beams or loadbearing members.

The invention is practiced in connection with a heated blank and themethod is completed before the blank has cooled to a degree suficient tointerfere. with the working of the metal. Preferably the invention ispracticed continuously with the delivery of the blank from a standardmill pass and the method is commenced with the blank at or near thedegree of heat which it has at the delivery stage of the rollingoperation.

The principal objects of the invention are to provide a method havingthe characteristics generally indicated and which is simpler and morerapid than methods heretofore pro posed and may be practiced with morecompact and less expensive equipment; and to obtain a product ofsuperior form and quality.

Generally stated, the invention consists in the correlation of steps ofproviding slits in the blank and of elongating the strands such thatthey are performed as parts of a single operation and that the extent ofstrand elongation and resultant expansion may be con- 5 trolled byelements involved in the provision of the slits, the resultant productbeing one in which the strands are uniformly homogeneous as to theirmiscrostructure and proportions. Instead of slitting the blank in theordinary manner, that is to say by cutters which have a shearing actionand which bodily displace and to some extent initially stretch thestrands, thereby producing effects which must be overcome in anypractically successful method and which add to the complexity of themethod and of the equipment for its practice, I propose to treat theblank in such manner as to form the slits and simultaneously to displacelaterally, in determined degree, some of the metal of the strands,without, however, stretching the strands. Such treatment of the blank isaccompanied by the rolling of the strands simultaneously with theformation of the slits by which the strands are delimited, the metaldisplaced by the slit-forming operation being utilized for theelongation of the strands whereby the strands may have the samethickness which they had in the blank and the extent of elongation isproportionate to the amount of metal which is displaced by theslit-forming operation. One way of carrying out this treatment and whichis herein shown is to score the blank by parts which have a wedge-likeaction and which form rows of slits whereby as the slits are formed apercentage of metal, which may be determined as desired, is deposited orcaused to accumulate or lodge on the parts, i. e. the strands, betweenthe rows of slits. During the elongation of the strands the width of theblank is successively and progressively increased between portions ateach side which are not subject to the scoring and rolling actions,thereby simultaneously to compensate and continuously take up theelongation of the rolled portion at a rate corresponding to that of theelongation and wlth resultant expansion of the blank. of the blank maybe effected in different ways and is herein shown as effected byspreading or fanning out the unrolled side portions. The method is thusone which may be completed in a single roll pass and in which no warping0r buckling of the metal is produced or permitted. Moreover, there areno factors by which inequalities in form or physical characteristics areintroduced or by which, as compared with cold expanding operations, anyinternal stresses are developed. It fol lows that the product is one inwhich the elongated strands and bonds are uniform in thickness,dimensions, physical qualities and microstructure, and may lie in planescoincident with the mean or general plane of the expanded article.

As applied to load bearing members the web is treated as above indicatedand simultaneously rolled in the manner abcve generally described whilethe remain of The increase in the width line of the same length as inthe blank and during the elongation of the strancs are simultaneouslyand progressively and at a rate proportionate to the elongation spreador fanned out so as to compensate the elongation as it occurs and ithresultant expansion of the blank into the load bearing member which, ifdesired, although this not strictly necessary, may be passed throughfinishing rolls.

The above and other characterizing features of the invention will be setforth in detail as the description proceeds and will appear from theaccompanying drawings which illustrate apparatus by which. the methodmay be practiced, the steps in the evolution of the blank into thecompleted product, and a portion of an expanded beam produced by themethod.

In said drawings:

Figure 1 is a plan view of the apparatus showing a'blank in tl e courseof expansion.

Figure 2 is an end elevation of the guides which are used in theexpansion of the blank, th being viewed at the ends at which on pensionis completed.

F igure 3 is a cross-section of the rolls and of the part of the blankin the roll pass.

Figure i is a developed plan view of the bottom roll.

Figure 5 is a developed plan view of the top roll.

Figure 6 is a cross-section of the blank. F gure 7 is a cross-section ofthe blank elongation of the strands is in progress.

Figure 8 is a cross-section of the finished load bearing member.

Figure 9 is a fragmentary elevation of the finished load bearing member.

Figure 10 is a cross-section of rolls of al ternative form and of thepart of the blank in the roll pass.

The method nreferabl practiced continuously and in connection with therolling of the blank.

in such case the heat of the blar as it comes from the stand of the mill2 which its development has beebrought to the stage desired utilized.and the method is completed with final determin tion of the and physicalqualities of the expander arti :lc while the blank is yet suilicientlyhot for its parts to be worked and relocated.

The method is applicable to different fornis of beams one ot expandedarticles and is herein illustrated in. connection with the production ofa beam in the form of a simple lattice truss wherein the struts have asingle intermediate bonds representing points of intersection, theremaining bonds being the connections between the struts and the chords,that is to say, the panel points of the truss. p

The blank E (Figure 6) is shown as having a crosssection generallysimilar to that of a standard I-beam and is provided with parallelflanges 2 and a web 3 which have been suit-bly developed I an antecedentrolling operation.

' J ln this iorni the blank may be passed directly from the mill stand(not shown) to the apparatus oy which he present methoeis practiced.

Such apparatus, as shown in F igures 3, l and 5, consists essentially ofa pair of cooperating upper and lower rol s 11 and 12 which not both toslit the blank and to elongate the resultant strands. The slitting maybe accomplished by a scoring operation for the purpose of which therolls 11 and 12 are formed with suitable scoring ribs 13 and 14respectively. The beam may within practical limits have any desirednumber of rows of struts and bonds and the number and arrangement of theribs 13 and i l may varied accordingly, the'arrangement shown beingadapted for a simple lattice truss and providing for three rows of slitsdeveloped along parallel lines with the slits of the intermediate rowstaggered relatively to the slits of the two outer rows.

In the construction shown in Figs. 3, l and 5 the rios13 and l t areformed to penetrate the blank for its full thickness, the ribs 14 whichprovide the outer rows of slits being arranged in two rows andpenetrating the web from below and the ribs 13 which provide theintermediate row of slits being a "ranged in a single row andpenetrating the web from above. In addition to the scoring ribs therolls are formed *ith working surfaces which operate on the upper-andlower faces of the strands delimited by the slits and which in theircooperating relation are parallel in the two rolls in the transversedirection. In the construction shown in Fig. 8 these working surfacesare laterally inclined or beveled. Tie upper roll 11 isformed withworking surfaces 15 and 16 which are, respectively, at opposite sides ofthe row of ribs 13, tl ese surfaces extending transversely between thebases of the ribs 13 and lines which coincide peripherally with theapices of the ribs 1d. The lower roll 12 is formed with workin gsurfaces 17 and 18 which lie between the rows of ribs 14". and extendtransversely between the bases of said ribs and a line coincidingperipherally with the apices of the ribs 13. The working surfaces aremutually cooperative in pairs, one of which consists of the surfaces 15and 17 and the other of surfaces 16 and 18, the working surfaces of eachcoopeating pair being inclined oppositely in the lateral direction fromthe working surfaces of the other pair. This arrangement of the workingsurfaces is of advantage where the scoring ribs penetrate the web forits full thickness in that it facilitates the operation of such ribs byproviding opposite the apices thereof a thin bearing; .line from whichthe working surfaces rec-eds, thereby developing a tendency to break theweb along longitudinal lines coinciding with thelinesof scoring and inthis way minimizing the resistance to the action of the scoring ribs. Afurther advantage of the transversely inclined working surfaces is thatthe strands or struts as rolled are at such angles, transversely, thatthe axes about which they are bent during expansion is of minimumtransverse depth so that mini mum resistance to the bending action isinterposed with resultant lessening of the force required to producesuchbending action and of the liability of tea-ring at the bonds.

The ribs 13 and 14 are of triangular crosssection with sharply definedapices and penetrate the web with a wedging action, thus scoring the weband providing for the slits which are necessary for the expansion of theblank. In respect to the material of the Web which is confined betweenthe ribs, that is to say the strands delimited by the slits, the effectof the ribs, due to their wedge form and action, is to displacelaterally a. percentage of said material, the displaced material tendingto accumulate on the upper and lower faces of the strands just back ofthe center of the roll pass and proportionately to increase thethickness of the strands. However, the depth of the roll pass asdetermined by the distances perpendicularly between the cooperatingworking faces, that is to say the faces 15 and 17 of one pair and thefaces 16 and 18 of the other pair is less than the increased depth ofthe strands and is preferably no greater than the original thickness ofthe web from which it follows that said Working faces act on the excessmetal displaced by the scoring ribs and proportionately elongate thestrands without reducing their thickness, the displaced metal being thusused to provide for the elongation. The accumulation of displaced metalon the parts between the rows of slits commences as soon as the scoringribs penetrate the blank and reaches its maximum at or substantially atthe common center line of the rolls.

The percentage of metal displaced by the scoring ribs will depend on theangles of the sides of the ribs. By suitable selection of such anglesthe percentage of displaced metal can be varied and since the elongationis proportionate to the percentage of metal displaced the elongation canbe correspondingly varied. Thus the angles of the sides of the ribs canbe utilized to determine the elongation of the strands; for example, ifa twenty percent elongation of the strands be desired the angles of thescoring ribs will be selected to displace twenty percent of the metal ofthe strands. If desired the elongation of the strands in the mannerdescribed may be modified by regulation of the depth of the roll pass.Thus instead of having the roll pass of the same depth as the thicknessof the web it may be of slightly greater depth (but still less than theincreased thickness of the strands caused by the accumulation ofdisplaced metal) in which case the elongation of the strands will beproportionately reduced and the strands will be slightly thicker thanthe original thickness of the web or it may be of slightly less depth inwhich case the elongation of the strands will be proportionatelyincreased and the strands will be of proportionately less thickness thanthe original thickness of the web.

The web on emergence from the roll pass will, owing to the elongation ofthe strands, travel at a greater rate than the blank as it approachesthe roll pass, the increase of speed being proportionate to thepercentage of elongation. For example, if the speed of the blank up tothe reducing rolls be 100 feet per minute and a twenty-five percentelongation be provided for the speed of the Web on emergence from theroll pass will be 125 feetper minute. To compensate this elongation ofthe web relatively to the unelongated flanges which of course travel ata uniform rate the scoring and elongating rolls are employed incooperation with means for initiatin g and controlling an increase inthe width of the blank simultaneously and continuously with theelongation of the web, at a proportionate rate and in a proportionatedegree. In the embodiment disclosed such means is constituted by shoes19 and flange guides 20 (Figures 1 and 2). The shoes 19 are preferablyprovided in upper and lower pairs, one pair being associated with eachscoring and elongating roll, and the the shoes of each pair havingforwardly divergent guide faces 21 which bear against the inner faces ofthe flanges 2, with inclination of the faces 21 being determined inaccordance with the requirements previously stated, that is to say tocontrol the spreading or fanning out of the flanges at a rateproportionate to the elongation. The shoes 19 preferably engage theflanges substantially at or slightly ahead of the center lines of therolls whereby they commence to act on the flanges substantially at thetime of the application of pressure to the strands by the working facesof the rolls. Owing to the scoring operation the walls of the slits havetheir closest approach to one another only along lines substantiallyflush with a face of the web and, receding from such lines, are widelyseparated throughout the thickness of the web. Any tendency for thewalls of the slits to freeze or weld due to the pressure of the workingfaces of the rolls is limited to the narrow lines from which the wallsof the slits recede and is immediately counteracted and with a minimumof force by the initial action of the shoes 19 which thus insure thatduring expansion no stresses are imposed on the panel point bondproviding portions such as might arise if it were necessary to separateany adjacent strands which had become partially welded.

The lateral deflection of the flanges initiated by the shoes 19 ispractically continued by the strands themselves which, elongating at anangle to the direction of travel, (Figures 1 and 7 act somewhat in themanner of a toggle to move the flanges relatively outward, thisspreading of the flanges being thus effected with minimum resistance andbeing controlled by the shoes 19. It will thus be noted that thespreading of the flanges is not resorted to for the purpose ofelongating the struts and has no effect on the length of the struts butis in consequence of the elongation of the struts and is so controlledthat the elongation of the web is continuously and proportionatel rcompensated with reference to the unelongated flanges so that there isno tendency for the struts to buckle or to shear or partially shear fromthe adjacent chord portions. The spreading or fanning out of the flangesin connection with the elongation and lateral deflection of the strutsresults in the formation of the web into open Work to the degreerequired in the completed prodct. lVhen the lateral deflection of thestrands has proceeded as far as may be desirable the action is arrestedby the guides 20 which have parallel faces to engage the outer faces ofthe flanges 2 and direct said flanges along parallel lines. The guides20 are effective at the time the elongation of the strands is completedand the product on emergence from said guides is the completed beam(Figures 1, 8 and 9), all parts of which travel at the same speed as theoriginal blank. If desired the beam may pass from the guides 20 tofinishin rolls (not shown) in order to eliminate any surfaceirregularities but this is not strictly necessary.

Figure 10 shows an alternative form of the web scoringand elongatingrolls which, as in the embodiment described, are provided in a singlepair and are employed in connection with the shoes 19 and guides 20. Themodification consists in the form and arrangement of the scoring ribsand the working roll faces according to which the action proceeds withthe strands in the original plane of the web instead of being oppositelyinclined relatively to such plane as in the embodiment described.

The rolls 11f and 12 of Figure 10 are formed with peripherallycoincident scoring ribs 22 arranged in three rows to produce three rowsof slits as in the embodiment described, it being of course understoodthat as many rows as desired may within practical limits be provided.The ribs 22 have the characteristic wedge form and action abovedescribed but penetrate the web for only half its thickness, thepenetration being simultaneous from both faces of the web. These rollshave working faces 23 which eX- tend between the bases of the ribs andare parallel, laterally, to the plane of the web.

As in the embodiment described the ribs displace a percentage of themetal which is confined between them and this percentage, which dependson the angles of the sides of the ribs, tends to accumulate on the webback of the roll pass and is utilized by the worklng faces 23 to effectthe elongation of the strands, the action being similar to thatdescribed.

laving fully described my invention I claim:

1. The method of expanding metal which includes the steps of treatingaheated blank to form slits along parallel rows and simultaneously so todisplace a percentage of the metal of the blank as to cause the same tolodge on the surfaces of the parts lying between the rows of slits andimmediately during the formation. of the slits rolling the blank toelongate the parts between the cleveloping slits and upon which thedisplaced metal has lodged.

2. Che method of expanding metal which is characterized by so slitting aheated blank to provide rows of slits as a part of an operation ofrolling the metal between the rows of elite to displace a percentage ofthe metal cause the same to lodge upon the parts to be rolled.

3. The method of expanding metal which includes the steps effected in asingle roll pass of so slitting a heated blank in rows as to displacemetal and cause the lodgment of the same upon the parts between the rowsof slits and rolling the parts upon which the displaced metal haslodged, thereby to elongate said parts. 7

a. The method of expanding metal which consists of the steps effected ina single roll pass of so slitting a heated blank in rows as to displacemetal and cause the lodgment of the same upon the parts between the rowsof slits and rolling the parts upon which the displaced metal haslodged, thereby to elongate said parts, and the further step oflaterally deflecting the rolled parts immediately on their emergencefrom the roll pass to cause an increase in the width of the blankprogressive with and proportionate to the elongation.

5. The method of expanding metal which consists of treating a heatedblank to form slits along parallel rows and simultaneously so todisplace a determined percentage of the metal of the blank as to causethe same to lodge on the surfaces of the parts lying between the rows ofslits, rolling the blank to elongate the parts upon which the dis placedmetal has lodged and laterally deflect ing the rolled parts continuouslyduring their elongation and at a proportionate rate.

6. The method of expanding metal which includes the steps of so scoringa heated blank in rows as to form slits and producean accumulation ofdisplaced metal on the parts of the blank between the rows of slits andso rolling the metal between the rows of slits immediately during theformation of the slits as to utilize the displaced metal for theelongation of the rolled parts.

7. The method of expanding metal by rolling and elongating parts betweenrows of slits in a heated blank wherein the blank is scored to providethe slits and the scoring operation is utilized to predetermine thepercentage of elongation by causing the displacement of a determinedpercentage oi the metal of the blank on the portions thereof between theslits.

8. The method of expanding metal which includes the steps of scoring androlling a heated blank in a single roll pass to form rows of slits andelongate the parts between the rows of slits.

9. The method of expanding metal which consists of the steps of scoringand rolling a heated blank in a single roll pass to form rows or" slitsand elongate the parts between the rows of slits, and of laterallydeflect ing the rolled parts immediately on their emergence from theroll pass to cause an increase in the width of the blank progressivewith and proportionate to the elongation.

10. The method of expanding metal which consists of so scoring a heatedblank in rows as to form slits and produce a determined accumulation ofdisplaced metal on the parts of the blank between the rows of slits, sorolling the metal between the rows of slits as to utilize the displacedmetal for the elongat-ion of the rolled parts, and laterally deflectingthe rolled parts continuously during their elongation and at aproportionate rate.

11. The method of expanding metal which is characterized by effecting awedge-like scoring action on a heated blank as apart of an operation ofelongating by rolling and to provide rows of slits.

12. The method of expanding metal which is characterized by eflecting awedge-like scoring action on a heated blank as a part of an operation ofelongating by rolling whereby to provide rows of slits and to deposit onthe parts between the slits a percentage of displaced metal by which theelongation eftected by the rolling is determined.

13. The method of making an expanded load bearing member from a heatedflanged rolled blank which includes the steps eftected in a single rollpass of so slitting the web in rows as to displace metal and cause thelodgment of the same upon the parts between the rows of slits androlling the parts upon which the displaced metal has lodged, thereby toelongate said parts, and the further step of laterally deflecting therolled parts continuously during their elongation and at a proportionaterate, thereby to form the web into open work.

14. The method of making an expanded load bearing member from a heatedflanged rolled blank which consists of the steps ef- :tected in a singleroll pass of so slitting the web inrows as to displace metal and causethe lodgment of the same upon the parts between the rows of slits androlling the parts upon which the displaced metal has lodged, thereby toelongate said parts, and the further steps of laterally deflecting therolled parts continuously during their elongation and at a proportionaterate, thereby to form the web into open work, and of arresting thelateral deflection on the termination of the elongation, thereby todeliver from said roll pass a complete expanded beam.

15. The method of making an expanded load bearing member from a heatedflanged rolled blank which includes the steps of so scoring the web ofthe blank in rows as to form slits and produce an accumulation ofdisplaced metal on the parts of the web between the rows of slits and sorolling the metal between the rows of slits immediately during theformation of the slits as to utilize the displaced metal for theelongation of the rolled parts. I

16. The method of making an expanded load bearing member from a heatedflanged rolled blank which includes the steps of scoring and rolling theweb of the blank in a single roll pass to form rows of slit-s andelongate the parts between the rows of slit-s, and of laterallydeflecting the rolled parts immediately on their emergence from the rollpass to cause an increase in the width of the blank progressive with andproportionate to the elongation, thereby to form the blank into openwork.

17. The method or" making an expanded load bearing member from a heatedflanged rolled blank which consists of the steps of scoring and rollingthe web of the blank in a single roll pass to form rows of slitsandelongate the parts between the slits, of laterally deflecting therolled parts immediately on their emergence from the roll pass to causean increase in the width of the blank progressive with and proportionateto the elongation, thereby to form the blank into open work, and ofarresting the lateral deflection on the termination of the elongation,thereby to deliver from said roll pass a complete expanded beam.

In testimony whereof I hereby aflix my signature.

HARVEY M. GERSMAN.

